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Questions about New QHY16200

Questions about New QHY16200
« on: November 27, 2017, 01:41:29 AM »
I received my new QHY16200.  Very impressive product.  I did have a couple of questions after I hooked it up to take some calibration images tonight:

What should the gain and offset be set too?  I'm at 0 and 135 right now and the histogram for bias is about 1600 and it saturates at about 64500.  This seems correct?

I'm getting a read noise of about 11.8e assuming gain 0=.7e in low speed mode.   High speed mode appears to actually be about the same. Is there any advantage of using low speed?

It appears the camera doesn't have a butterfly shutter but a standard flap shutter.  Is this a recent change?

My dark frames appear to have a cross on them.  I assume this will calibrate out?  See image below.



 

 

Wandering Sand

Re: Questions about New QHY16200
« Reply #1 on: November 27, 2017, 04:44:11 AM »
The camera has always been butterfly shutter. I made a error before. See the attachment.
ABOUT other question, I will ask others to answer.



I received my new QHY16200.  Very impressive product.  I did have a couple of questions after I hooked it up to take some calibration images tonight:

What should the gain and offset be set too?  I'm at 0 and 135 right now and the histogram for bias is about 1600 and it saturates at about 64500.  This seems correct?

I'm getting a read noise of about 11.8e assuming gain 0=.7e in low speed mode.   High speed mode appears to actually be about the same. Is there any advantage of using low speed?

It appears the camera doesn't have a butterfly shutter but a standard flap shutter.  Is this a recent change?

My dark frames appear to have a cross on them.  I assume this will calibrate out?  See image below.



 
« Last Edit: November 29, 2017, 01:50:04 AM by ZY »

Re: Questions about New QHY16200
« Reply #2 on: November 27, 2017, 10:26:37 PM »
The camera originally have a standard flap shutter. 
ABOUT other question, I will ask others to answer.



I received my new QHY16200.  Very impressive product.  I did have a couple of questions after I hooked it up to take some calibration images tonight:

What should the gain and offset be set too?  I'm at 0 and 135 right now and the histogram for bias is about 1600 and it saturates at about 64500.  This seems correct?

I'm getting a read noise of about 11.8e assuming gain 0=.7e in low speed mode.   High speed mode appears to actually be about the same. Is there any advantage of using low speed?

It appears the camera doesn't have a butterfly shutter but a standard flap shutter.  Is this a recent change?

My dark frames appear to have a cross on them.  I assume this will calibrate out?  See image below.



 

Thanks!  When was the change made?  This is a new camera and all images I can find and your website say it should have a butterfly shutter. 

I'm more concerned about the large read noise value and cross on dark frames.

Re: Questions about New QHY16200
« Reply #3 on: November 28, 2017, 11:13:03 PM »
The camera originally have a standard flap shutter. 
ABOUT other question, I will ask others to answer.



I received my new QHY16200.  Very impressive product.  I did have a couple of questions after I hooked it up to take some calibration images tonight:

What should the gain and offset be set too?  I'm at 0 and 135 right now and the histogram for bias is about 1600 and it saturates at about 64500.  This seems correct?

I'm getting a read noise of about 11.8e assuming gain 0=.7e in low speed mode.   High speed mode appears to actually be about the same. Is there any advantage of using low speed?

It appears the camera doesn't have a butterfly shutter but a standard flap shutter.  Is this a recent change?

My dark frames appear to have a cross on them.  I assume this will calibrate out?  See image below.



 

Thanks!  When was the change made?  This is a new camera and all images I can find and your website say it should have a butterfly shutter. 

I'm more concerned about the large read noise value and cross on dark frames.

Figured this out.  Apparently the cap is a bit transparent and after I put a huge book in front and turned off the lights I was able to eliminate that glow.  Sorry about the false alarm.

Re: Questions about New QHY16200
« Reply #4 on: November 29, 2017, 12:28:52 AM »
By looking at the values on the histogram, it's correct, and your gain and off settings should be okay.

Talking about the advantage of low-speed mode, the readout noise in low-speed mode should be smaller than in high-speed mode. But it's normal that the noise in both modes are two close values because in low-speed mode during the readout process, the thermal noise would increase and it's affected by the temperature of CMOS sensor or the cooling condition.

Ryan

I received my new QHY16200.  Very impressive product.  I did have a couple of questions after I hooked it up to take some calibration images tonight:

What should the gain and offset be set too?  I'm at 0 and 135 right now and the histogram for bias is about 1600 and it saturates at about 64500.  This seems correct?

I'm getting a read noise of about 11.8e assuming gain 0=.7e in low speed mode.   High speed mode appears to actually be about the same. Is there any advantage of using low speed?

It appears the camera doesn't have a butterfly shutter but a standard flap shutter.  Is this a recent change?

My dark frames appear to have a cross on them.  I assume this will calibrate out?  See image below.



 

QiuHY

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Re: Questions about New QHY16200
« Reply #5 on: November 29, 2017, 04:33:57 AM »
Hello,

       After look the dark frame it looks there is some light leak.  So the readout data maybe not precise to use this image to do calculate.

       You can put the camera to a dark room to have a test to check if it is this leak.

Best regards,
Qiu Hongyun
Qiu Hongyun